Corn harvester

Abstract

A corn harvester has a chassis adapted to travel along the ground and provided on its front with an intake mechanism for picking ears off the cornstalks and for reducing these ears to fragments including pieces of cob, corn kernels, and pieces of husk. These fragments are displaced backwardly onto a ridged floor having a rear edge spaced by an upstream gap from a riddle having in turn a rear edge spaced upwardly by a downstream gap from a comb. A blower directs a current of air through these gaps to separate out the chaff-like husk pieces, while the smaller and denser fragments can drop through the riddle and be collected. Both the riddle and the floor are oscillated to displace the fragments backwardly. A second comb meshes with the first comb and has a plurality of tines that are continuously displaced through the tines of the first comb to separate out husk pieces from the fragments on the first comb. Thus only the corn kernels and pieces of cob will pass through the riddle or the first comb whereas the husk pieces will be separated out.

We claim: 
     
       1. A corn harvester comprising: a chassis adapted to travel along the ground;   means on the front of said chassis for picking ears off cornstalks;   means on said chassis for reducing said ears to fragments including pieces of cob, corn kernels, and pieces of husk, and for displacing said fragments backwardly;   a riddle on said chassis positioned to receive said fragments at least indirectly from the reducing means and having a rear edge;   a first comb on said chassis spaced by a gap below said rear edge of said riddle;   means for displacing said riddle and for moving said fragments backwardly with a portion of the smaller and denser fragments falling through said riddle and the rest of said fragments falling across said gap onto said first comb;   a second comb on said chassis meshable with said first comb;   means for displacing said second comb through said first comb and thereby separating said husk pieces from the rest of said fragments on said comb and for displacing the separated husk pieces away from said comb; and   means underneath said riddle and said comb for catching the fragments passing through same.   
     
     
       2. The harvester defined in claim 1, further comprising: a ridged floor between said reducing means and said comb and having a rear floor edge spaced vertically of a forward position of said riddle;   means for horizontally reciprocating said floor and thereby backwardly displacing fragments on said floor so that said fragments fall across said upstream gap onto said riddle; and   blower means for directing a current of air backwardly through at least said upstream gap thereby displacing the lighter fragments including mainly said husk pieces backwardly.   
     
     
       3. The harvester defined in claim 1, further comprising a curtain suspended from said chassis between said reducing means and said screen and positioned to intercept the fragments displaced backwardly by said reducing means. 
     
     
       4. The harvester defined in claim 3 wherein said curtain is provided with a forwardly open and backwardly pointed V-shaped stiffening element at its lower edge. 
     
     
       5. The harvester defined in claim 3 wherein said curtain has a lower edge provided with a generally straight stiffening element extending generally perpendicular to the normal direction of travel of said chassis, said chassis carrying a plurality of stops engageable with the ends of said stiffening element when said chassis is tipped, said stops being provided to both lateral sides of said stiffening element and being spaced apart by a transverse distance slightly greater than the transverse length of said stiffening element, whereby when said chassis is level said element can swing forwardly and backwardly between and out of contact with said stops. 
     
     
       6. The harvester defined in claim 1 wherein said second comb has a central rotatable and axis-defining second shaft extending generally horizontally and generally perpendicular to the normal direction of travel of said chassis and a plurality of generally radially extending second tines projecting from said shaft. 
     
     
       7. The harvester defined in claim 6 wherein said tines are angularly elastically deflectable on said shaft. 
     
     
       8. The harvester defined in claim 7 wherein said tines are of elastomeric material. 
     
     
       9. The harvester defined in claim 6 wherein said tines have radial inner ends secured to said shaft along a helix thereon, said tines extending screwthread-fashion from said shaft. 
     
     
       10. The harvester defined in claim 9 wherein said helix has two full turns around said shaft. 
     
     
       11. The harvester defined in claim 6 wherein said first comb includes a first shaft and a generally planar array of first tines projecting transversely from said first shaft. 
     
     
       12. The harvester defined in claim 11 wherein said first tines and second tines interleave on rotation of said second comb about the axis of said second shaft. 
     
     
       13. The harvester defined in claim 11, further comprising means for pivoting said first comb about the axis of said first shaft and for securing said first comb in any of a plurality of angular offset positions, whereby the extent to which the orbit of said second comb extends through said first comb can be adjusted. 
     
     
       14. The harvester defined in claim 6 wherein said second tines are inclined backwardly in the normal direction of rotation of said second comb. 
     
     
       15. The harvester defined in claim 6 wherein said second comb is rotated at a peripheral speed of at least 10 m/sec. 
     
     
       16. The harvester defined in claim 1, further comprising a curtain behind said combs and positioned to intercept said separated husk pieces from said second comb. 
     
     
       17. The harvester defined in claim 1 wherein said reducing means includes a rotatable reducing drum and spacedly juxtaposed therewith a grate. 
     
     
       18. The harvester defined in claim 17, further comprising means for rotating said drum relative to said grate, said grate having relative to the normal direction of rotation of said drum a leading edge and a trailing edge, the latter being spaced further from said drum than the former.